JP2011186460A - Toner particle and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide toner particles having improved heat cohesion properties. <P>SOLUTION: The toner particles include an amorphous resin, a crystalline resin, and a cyanine dye. The toner particles include the heat cohesion properties that are higher by 3-8°C than the particles without containing the cyanine dye. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present disclosure relates to an ultra-low-melt (ULM) toner composition having improved heat cohesion, a method of making such a toner composition, and such a toner composition. The present invention relates to a method of forming an image using

  ULM toners melt at very low temperatures, thus providing a toner system with relatively low energy requirements.

US Patent Application Publication No. 2009/0220882

  An object of the present invention is to provide toner particles having improved heat coherence and a method for producing the toner particles.

  The present invention is a toner particle that includes an amorphous resin, a crystalline resin, and a cyanine dye.

  The present invention also relates to toner particles comprising an amorphous resin, a crystalline resin, and a cyanine dye, wherein the toner particles are 3 ° C. to 3 ° C. higher than the corresponding toner particles not containing the cyanine dye. It is a toner particle having a heat cohesiveness of 8 ° C.

  The present invention is also a method for producing toner particles, wherein the method emulsifies an amorphous resin, a crystalline resin, a cyanine dye, an optional colorant, and an optional wax, A step of forming preliminary aggregated particles, a step of aggregating the preliminary aggregated particles to form aggregated particles, and a step of coreless the aggregated particles to form coreless particles. And a step of isolating the coreless particles.

  In some embodiments, the present disclosure provides a toner comprising an amorphous resin, a crystalline resin, and a cyanine dye, a method for producing such a toner, and an image using such a toner. And a method of forming the same. Cyanine dyes improve heat cohesion with little adverse effect on other desirable properties. For example, the toner thus obtained has acceptable charging performance and blocking properties.

  In this specification and in the claims that follow, singular forms such as "a", "an", and "the" also include the plural (if the content clearly indicates otherwise) Except). In addition, some terms that should be defined are as follows:

  The term “functional group” refers, for example, to a group of atoms arranged to determine the chemical nature of the group and the molecule to which it is attached. Examples of functional groups include halogen atoms, hydroxyl groups, carboxylic acid groups and the like.

  The terms “optional” or “optionally” refer, for example, to the case where a subsequent situation may or may not occur, and such a situation occurs. And cases where such a situation does not occur.

<Polymer (resin)>
The toner particles include at least one resin or a mixture of two or more resins. For example, the toner particles may include a styrene resin, a UV curable resin, and / or a polyester resin.

  Styrene resins and polymers are known to those skilled in the art. In some embodiments, specific styrene resins may be styrene-based polymers, including, for example, styrene acrylate-based polymers. Examples illustrating such resins are found, for example, in US Pat. No. 5,853,943, US Pat. No. 5,922,501, and US Pat. No. 5,928,829. be able to.

  UV curable resins are known to those skilled in the art. In some embodiments, the UV curable resin may be an unsaturated polymer that can be crosslinked in the presence of activating radiation, such as ultraviolet light, and a suitable photoinitiator. An example illustrating such a resin can be found, for example, in US Patent Application Publication No. 2008-0199797.

  Polyester resins are also known to those skilled in the art. Specific polyester resin or resins selected for the disclosure of the present invention include, for example, unsaturated polyesters and / or derivatives thereof, polyimide resins, branched polyimide resins, various polyesters such as crystalline polyesters, Amorphous polyester, or a mixture thereof may be mentioned. Examples illustrating such resins are found, for example, in US Pat. No. 6,593,049, US Pat. No. 6,756,176, and US Pat. No. 6,830,860. be able to.

  Examples of the crystalline resin include polyester, polyamide, polyimide, polyolefin, polyethylene, polybutylene, polyisobutylate, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polypropylene, a mixture thereof, and the like. Specific crystalline resins include those based on the following polyesters: poly (ethylene-adipate), poly (propylene-adipate), poly (butylene-adipate), poly (pentylene-adipate), poly (Hexylene-adipate), poly (octylene-adipate), poly (ethylene-succinate), poly (propylene-succinate), poly (butylene-succinate), poly (pentylene-succinate), poly (hexylene-succinate), poly (hexylene-succinate) Octylene-succinate), poly (ethylene-sebacate), poly (propylene-sebacate), poly (butylene-sebacate), poly (pentylene-sebacate), poly (hexylene-sebacate), poly (octylene-sebacate), alkaline copo (5-sulfoisophthaloyl) -copoly (ethylene-adipate), poly (decylene-sebacate), poly (decylene-decanoate), poly (ethylene-decanoate), poly (ethylene-dodecanoate), poly (nonylene-sebacate) , Poly (nonylene-decanoate), copoly (ethylene-fumarate) -copoly (ethylene-sebacate), copoly (ethylene-fumarate) -copoly (ethylene-decanoate), and copoly (ethylene-fumarate) -copoly (ethylene-dodecanoate) As well as combinations thereof.

  The crystalline resin may be present, for example, in an amount of about 5 to about 50% by weight of the toner component, such as about 10 to about 35% by weight of the toner component. The crystalline resin can have various melting points, such as from about 30 ° C to about 120 ° C, such as from about 50 ° C to about 90 ° C.

  Suitable amorphous resins include polyester, polyamide, polyimide, polyolefin, polyethylene, polybutylene, polyisobutyrate, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polypropylene, combinations thereof, and the like. Examples of amorphous resins include: poly (styrene-acrylate) resins, such as poly (styrene-acrylate) resins crosslinked from about 10% to about 70%, poly (styrene-methacrylate) resins, Crosslinked poly (styrene-methacrylate) resin, poly (styrene-butadiene) resin, crosslinked poly (styrene-butadiene) resin, alkali sulfonated polyester resin, branched alkali sulfonated polyester resin, alkali sulfonated Polyimide resin, branched alkali sulfonated-polyimide resin, alkali sulfonated poly (styrene-acrylate) resin, crosslinked alkali sulfonated poly (styrene-acrylate) resin, poly (styrene-methacrylate) resin, crosslinked alkali Sulfonation- Li (styrene - methacrylate) resins, alkali sulfonated - and the like - (butadiene-styrene) resins - poly (styrene-butadiene) resins, and crosslinked alkali sulfonated poly. Alkali sulfonated polyester resins are copoly (ethylene-terephthalate) -copoly (ethylene-5-sulfo-isophthalate), copoly (propylene-terephthalate) -copoly (propylene-5-sulfo-isophthalate), copoly (diethylene-terephthalate). ) -Copoly (diethylene-5-sulfo-isophthalate), copoly (propylene-diethylene-terephthalate) -copoly (propylene-diethylene-5-sulfoisophthalate), copoly (propylene-butylene-terephthalate) -copoly (propylene-butylene) -5-sulfo-isophthalate) and copoly (propoxylated bisphenol-A-fumarate) -copoly (propoxylated bisphenol A-5-sulfo-isophthalate) metal salts or al It may be used as the Li salt.

  Examples of other suitable latex resins or polymers include: poly (styrene-butadiene), poly (methylstyrene-butadiene), poly (methyl methacrylate-butadiene), poly (ethyl methacrylate- Butadiene), poly (propyl methacrylate-butadiene), poly (butyl methacrylate-butadiene), poly (methyl acrylate-butadiene), poly (ethyl acrylate-butadiene), poly (propyl acrylate-butadiene), poly ( (Butyl acrylate-butadiene), poly (styrene-isoprene), poly (methylstyrene-isoprene), poly (methyl methacrylate-isoprene), poly (ethyl methacrylate-isoprene), poly (propyl methacrylate-isoprene), poly (Methacrylic acid Chill-isoprene), poly (methyl acrylate-isoprene), poly (ethyl acrylate-isoprene), poly (propyl acrylate-isoprene), poly (butyl acrylate-isoprene); poly (styrene-propyl acrylate), Poly (styrene-butyl acrylate), poly (styrene-butadiene-acrylic acid), poly (styrene-butadiene-methacrylic acid), poly (styrene-butadiene-acrylonitrile-acrylic acid), poly (styrene-butyl acrylate-acrylic) Acid), poly (styrene-butyl acrylate-methacrylic acid), poly (styrene-butyl acrylate-acrylonitrile), poly (styrene-butyl acrylate-acrylonitrile-acrylic acid), and combinations thereof. These polymers may be block copolymers, random copolymers, alternating copolymers, and the like.

  Unsaturated polyester resins may be used as latex resins. Examples of unsaturated polyester resins include: poly (propoxylated bisphenol-co-fumarate), poly (ethoxylated bisphenol-co-fumarate), poly (butoxylated bisphenol-co-fumarate), poly (Co-propoxylated bisphenol-co-ethoxylated bisphenol-co-fumarate), poly (1,2-propylene fumarate), poly (propoxylated bisphenol-co-maleate), poly (ethoxylated bisphenol-co-) Maleate), poly (butoxylated bisphenol-co-maleate), poly (co-propoxylated bisphenol-co-ethoxylated bisphenol-co-maleate), poly (1,2-propylene maleate), poly (propoxylated) Bisfeneau -Co-itaconate), poly (ethoxylated bisphenol-co-itaconate), poly (butoxylated bisphenol-co-itaconate), poly (co-propoxylated bisphenol-co-ethoxylated bisphenol-co-itaconate), poly ( 1,2-propylene itaconate), and combinations thereof.

  A suitable amorphous polyester resin may be a poly (propoxylated bisphenol A-co-fumarate) resin having the following formula (I):

(I)
Wherein m may be from about 5 to about 1000. ]

  Examples of linear propoxylated bisphenol A fumarate resins that can be used as latex resins are from Resana S / A Industries Quimicas, Sao Paulo, Brazil, Brazil. It is available under the trade name SPARII. Other commercially available propoxylated bisphenol A fumarate resins include GTUF and FPESL-2 from Kao Corporation of Japan, and North Carolina Research Triangle Park (Research Triangle Park). EM181635 from Reichhold.

  Suitable crystalline resins include those disclosed in US Pat. No. 7,329,476 and US Pat. No. 7,510,811. The crystalline resin may comprise ethylene glycol having the following formula and a mixture of dodecanedioic acid and fumaric acid-co-monomer.

(II)
[Wherein b is from about 5 to about 2000 and d is from about 5 to about 2000. ]

  One, two or more toner resins / polymers may be used. In embodiments using two or more toner resins, the toner resin may be, for example, about 10% for the first resin and 90% for the second resin and about 90% for the first resin. The two resins may be present in various suitable ratios (eg, weight ratio) up to 10%. The amorphous resin used in the core may be linear. The amorphous resin may include a first amorphous resin and a second amorphous resin different from the first amorphous resin.

  The resin may be formed by an emulsion polymerization method, or may be a resin prepared in advance.

<Cyanine dye>
These toners may contain at least one cyanine dye or a mixture of two or more cyanine dyes. The cyanine dye should be dispersed as uniformly as possible throughout the toner particles. The cyanine dye serves to improve heat cohesion and in some cases also serves as an IR absorber.

Any suitable cyanine dye may be used. The cyanine dyes include the following: wherein ^{_{R 2 N + = CH [CH}} = CH] streptocyanines having n -NR ₂ (streptocyanine), wherein aryl ^{= N + = CH [CH =} CH] n -NR A hemicyanine having ₂ and a closed cyanine having the formula aryl = N ⁺ = CH [CH = CH] _n- N = Aryl, where n is an integer from about 1 to about 6; R ₂ is a substituted or unsubstituted alkyl group having from about 1 to about 20 carbon atoms, and Aryl is a substituted or unsubstituted aryl group. ].

  Cy3 dye and Cy5 dye may be used. The Cy3 dye has a maximum excitation at about 550 nm and a maximum emission at about 570 nm. The Cy5 dye has a maximum excitation at about 649 nm and a maximum emission at about 670 nm. These dyes are represented by the following general formulas (III) and (IV).

(III)

(IV)
[Wherein each R group is independently an aliphatic short chain, one or both of which may be reactive groups such as N-hydroxysuccinimide or maleimide. ]

  Examples of other cyanine dyes include those having the following formula (V).

(V)
[Where:
R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , and R ₈ are each independently hydrogen, C ₁ -C ₆ alkyl groups, sulfonates, carboxylates, hydroxyls, substituted amines and Selected from the group consisting of C ₀ -C ₄ alkyl groups having a hydrophilic substituent selected from the group consisting of quaternary amines, so that at least one of R ₁ -R ₈ , R ₁₁ and R ₁₂ is hydrophilic A C ₀ -C ₄ alkyl group having a functional substituent;
Y ₁ and Y ₂ are each independently composed of a carbon atom, an oxygen atom, nitrogen, sulfur, and a group such as —S—C—, —N═C—, —O—C—, —C—C—, and the like. it is selected from the group, wherein these atoms or groups, C ₁ -C ₆ alkyl C ₁ -C ₆ alkyl or heteroatom substituted (the hetero atom is O, N or S) are further substituted with Can be;
R ₁₁ and R ₁₂ are each independently selected from the group consisting of R ₁₄ H, R ₁₄ SH and R ₁₄ OH, wherein R ₁₄ is C ₃ -C ₃₀ alkyl, and phenyl, hydroxyl, sulfonyl Or selected from the group consisting of C ₃ -C ₃₀ alkyl having a halogen atom, or heteroatom-substituted phenyl; and L is methine, a methine group having a substituent C ₁ -C ₃₀ alkyl group, and phenyl, hydroxyl, sulfonyl, halogen atom, is selected from the group consisting of a methine group having a substituted _C 1 _{-C 30} alkyl group having a phenyl or _C 1 -C ₄ alkoxyl heteroatoms substituted, wherein the dye or hapten (hapten ) As active ingredients according to the instructions for using them as n Is 1, 2, 3 or greater. ]

  Specifically, examples of the cyanine dye include those having the following formula (VI).

(VI)
[Where:
n is 0, 1, or 2;
R ₁ and R ₃ are independently substituted or unsubstituted alkyl groups having from about 1 to about 20 carbon atoms, such as methyl, ethyl, propyl, butyl, etc .;
R ₂ is selected from the group consisting of halogen, hydrocarbon groups containing 1 to about 18 carbon atoms, heteroatom-containing groups such as thienyl groups and amino groups;
X ⁻ may be any suitable counter ion, such as BF ₄ ⁻ , Cl ⁻ , ClO ₄ ⁻ , Br ⁻ , I ^{−, and the} like; and about 4 to about 4 for the cyclic groups (substituted or unsubstituted) at both ends. Contains 28 carbon atoms. ]

  Examples of cyanine dyes include those of the following formula.

1-butyl-2- (2- [3- [2- (1-butyl-1H-benzo [cd] indol-2-ylidene) -ethylidene] -2-phenyl-cyclopent-1-enyl] -vinyl)- Benzo [cd] indolium tetrafluoroborate, commercially available as S-0813 from FEW Chemicals GmbH, FEW Chemicals GmbH, Germany;

Commercially available as NK2911 from Hayashibara Biochemical laboratories, Inc. in Japan; and

It is commercially available as NK4680 from Hayashibara Biochemical laboratories, Inc. of Japan.

  The cyanine dye may be in various effective amounts in the toner, such as from about 0.01 to about 5% by weight of the toner, such as from about 0.02 to about 3%, or from about 0.05 to about 2%, or about It may be present in an amount of 0.1 to about 1% by weight.

<Surfactant>
In some embodiments, one, two or more surfactants are used to contact the resin, cyanine dye, and / or other ingredients with one or more surfactants. An emulsion may be formed. Those surfactants may be selected from ionic surfactants and nonionic surfactants. The term “ionic surfactant” includes anionic surfactants and cationic surfactants. The surfactant may be present in an amount of about 0.01 to about 5%, such as about 0.75 to about 4%, or about 1 to about 3% by weight of the toner composition.

  Examples of nonionic surfactants include, for example, from Rhone-Poulenc, IGEPAL CA-210 ™, IGEPAL CA-520 ™, IGEPAL CA-720. (Trademark), IGEPAL CO-890 (trademark), IGEPAL CO-720 (trademark), IGEPAL CO-290 (trademark), IGEPAL CA-210 (trademark), Antalox (ANTAROX) 890 ™, and those commercially available as ANTAROX 897 ™. Other examples include block copolymers of polyethylene oxide and polypropylene oxide, including those commercially available as SYPERONIC PE / F, such as SYPERONIC PE / F108.

  Suitable anionic surfactants include Neogen R (trademark), Neogen SC (trademark), combinations thereof, and the like obtained from Daiichi Kogyo Seiyaku. . Other suitable anionic surfactants include, in some embodiments, DOWFAX ™, an alkyldiphenyl oxide disulfonate from The Dow Chemical Company. ) 2A1 and / or TAYCA POWER BN 2060, a branched sodium dodecyl benzene sulfonate from Tayca Corporation (Japan). These surfactants and the aforementioned various anionic surfactants may be used in combination.

  Examples of suitable cationic surfactants that are normally positively charged include, for example, MIRAPOL ™ and ALKAQUAT ™ available from Alkal Chemical Company, for example. ), SANIZOL ™ (benzalkonium chloride) available from Kao Chemicals, and the like, and mixtures thereof.

<Wax (release agent)>
The toner particles may include one or more waxes. In these embodiments, the emulsion includes the resin and wax particles at the desired loading level, so that a single resin and wax emulsion are present rather than separate resin and wax emulsions. Will be obtained. However, the wax may be separately emulsified with, for example, a resin and separately incorporated into the final product.

  In addition to the polymer binder resin, the toner may further comprise a wax, either a single type of wax, or a mixture of two or more preferably different waxes. For example, a single wax may be added to the toner formulation to determine certain properties of the toner, such as toner particle shape, presence and amount of wax on the toner particle surface, charge and / or fusing performance, gloss, peelability (Stripping), offset performance and the like can be improved. Alternatively, various properties can be imparted to the toner composition by adding a combination of waxes.

  Suitable examples of waxes include waxes selected from natural vegetable waxes, natural animal waxes, mineral waxes, synthetic waxes, and functionalized waxes. Examples of natural vegetable waxes include, for example, carnauba wax, candelilla wax, rice wax, urushi wax, jojoba oil, wood wax, and barberry wax. Examples of natural animal waxes include, for example, beeswax, punic wax, lanolin, lac wax, shellac wax, and whale wax. Mineral based waxes include, for example, paraffin wax, microcrystalline wax, montan wax, ozokerite wax, ceresin wax, petrolatum wax, and petroleum wax. Synthetic waxes include, for example, Fischer-Tropsch wax; acrylate wax; fatty acid amide wax; silicone wax; polytetrafluoroethylene wax; polyethylene wax; ester wax obtained from higher fatty acid and higher alcohol, such as stearyl stearate and behenic acid Behenyl; ester waxes derived from higher fatty acids and mono- or polyhydric lower alcohols, such as butyl stearate, propyl oleate, glyceride monostearate, glyceride distearate, and pentaerythritol tetrabehenate; Ester waxes obtained from polyhydric alcohol multimers, such as diethylene glycol monostearate, dipropylene glycol distearate Diglyceryl distearate, and triglyceryl tetrastearate; sorbitan higher fatty acid ester waxes, such as sorbitan monostearate; and cholesterol higher fatty acid ester waxes, such as cholesteryl stearate; polypropylene wax; and mixtures thereof.

  In some embodiments, the wax may be selected from: Polypropylene and polyethylene (eg, Bakers) commercially available from Allied Chemical and Baker Petrolite. POLYWAX ™ polyethylene wax from Baker Petrolite, a wax emulsion commercially available from Michaelman Inc. and Daniels Products Company, Eastman Chemical Products Inc. (Eastman Chemical) EPOLENE N-15 commercially available from Products, Inc., low weight average molecular weight polypropylene of VISCOL 550P commercially available from Sanyo Kasei K.K., and Similar substances. Commercially available polyethylene usually has a weight average molecular weight Mw of about 500 to about 2,000, for example about 1,000 to about 1,500, whereas commercially available polypropylene has a weight average molecular weight Mw of about 1, It has a molecular weight of 000 to about 10,000. Examples of functionalized waxes include amines, amides, imides, esters, quaternary amines, carboxylic acids, or acrylic polymer emulsions such as JONCRYL 74, 89, 130, 537, and 538 (all Johnson Divers Available from Johnson Diversity, Inc., Allied Chemical and Petrolite Corporation, and commercially available from Johnson Diversity, Inc. Chlorinated polypropylene and polyethylene.

  Wax is used for the toner on a dry basis, for example from about 1 to about 25% by weight of toner, such as from about 3 to about 15% by weight of toner, or from about 5 to about 20% by weight of toner, for example from about 5 to about 5% of toner. It may be included in an amount of about 11% by weight.

<Colorant>
The toner particles may further contain at least one colorant. For example, colorants or pigments used herein include pigments, dyes, mixtures of pigments and dyes, mixtures of pigments, mixtures of dyes, and the like. For simplicity, the term “colorant” as used herein is intended to encompass such colorants, dyes, pigments, and mixtures, but specific pigments or other colorants. It is different when an agent is specified. The colorant may be included in an amount of about 0.1 to about 35% by weight, such as about 1 to about 25% by weight, based on the total weight of the composition.

<Coagulant (coagulant)>
The emulsion aggregation process for producing the toner disclosed in the present invention uses at least one coagulant, such as a monovalent metal coagulant, a divalent metal coagulant, a polyion coagulant, and the like. As used herein, the term “polyion coagulant” refers to a salt or oxide, eg, a metal salt or metal oxide formed from a metal species having a valence of at least 3, at least 4, or at least 5. Means coagulant. Suitable coagulants include, for example: aluminum-based coagulants such as polyaluminum halides such as polyaluminum fluoride and polyaluminum chloride (PAC), polyaluminum silicates such as aluminum polysulfosilicate (PASS) , Polyaluminum hydroxide, aluminum polyphosphate, aluminum sulfate and the like. Other suitable coagulants include (but are not limited to): tetraalkyl titanates, dialkyl tin oxides, tetraalkyl tin oxide hydroxides, dialkyl tin oxide hydroxides, aluminum alkoxides, alkyls Zinc, dialkyl zinc, zinc oxide, stannous oxide, dibutyl tin oxide, dibutyl tin oxide hydroxide, tetraalkyl tin and the like. When the coagulant is a polyion coagulant, the coagulant may have various desired numbers of polyion atoms. For example, in some embodiments, suitable polyaluminum compounds have from about 2 to about 13, such as from about 3 to about 8 aluminum ions present in the compound.

  Such coagulants can be incorporated into the toner particles during particle aggregation. By doing so, the coagulant is included in the toner particles, excluding external additives and on a dry weight basis, in an amount of 0 to about 5% by weight of the toner particles, for example more than about 0 of the toner particles. It can be present in an amount up to about 3% by weight.

<Emulsion aggregation process>
In order to form toner particles, any suitable emulsion aggregation process may be used or modified without any particular limitation. The emulsion aggregation process generally includes the steps of emulsification, aggregating, coalescing, washing, and drying. For example, US Pat. Nos. 5,278,020 and 7,029,817 as well as US Patent Application Publication No. 2008/0170989 disclose emulsion aggregation toners. Specification is mentioned. These procedures may be modified to facilitate the inclusion of cyanine dyes and to improve heat cohesion.

  Thus, in some embodiments, the emulsion aggregation process may include the following basic process steps: polymer binder, cyanine dye, optional wax, optional colorant, surfactant, and Aggregating an emulsion containing an optional coagulant to form an aggregated particle; Freezing the growth of the aggregated particle; Corelessing the aggregated particle to form a coreless particle Then the toner particle isolation step, optionally a cleaning step, and optionally a drying step.

[Formation of emulsion]
If the resin and the cyanine dye have similar solubility parameters, the same solvent can be used to dissolve the resin and the cyanine dye to make a solution as homogeneous as possible. The resin and the cyanine dye may be emulsified with each other. However, if the resin emulsion and the cyanine dye emulsion are not prepared simultaneously, the resin may be added to the prepared cyanine dye emulsion, the cyanine dye may be added to the prepared resin emulsion, or The prepared cyanine dye emulsion may be added to the prepared resin emulsion. Emulsification of the emulsion may be carried out mechanically or chemically.

  For example, phase inversion emulsification (PIE) may be used, in which case both the cyanine dye and the resin are dissolved in a suitable solvent. Water may be added to the solvent until separation of the solvent and water occurs under mixing. The solvent may be removed by vacuum distillation, resulting in an emulsion in water of the polymer and the cyanine dye micro-sphere.

  An emulsion may be prepared by dissolving the resin and / or cyanine dye in a solvent. Suitable solvents include alcohols, ketones, esters, ethers, chlorinated solvents, nitrogen-containing solvents, and mixtures thereof. Specific examples of suitable solvents include isopropyl alcohol, acetone, methyl acetate, methyl ethyl ketone, tetrahydrofuran, cyclohexanone, ethyl acetate, N, N-dimethylformamide, dioctyl phthalate, toluene, xylene, benzene, dimethyl sulfoxide, and their It is a mixture. The resin / cyanine dye may be dissolved in the solvent at an elevated temperature of about 40 ° C to about 80 ° C, such as about 50 ° C to about 70 ° C, or about 60 ° C to about 65 ° C. The resin / cyanine dye is at a temperature below the boiling point of the solvent, such as about 2 ° C. to about 15 ° C., or about 5 ° C. to about 10 ° C. below the solvent boiling point, and above the glass transition temperature of the resin / cyanine dye. It may be dissolved at a low temperature.

  After dissolving in a solvent, the dissolved resin / cyanine dye may be mixed into an emulsion medium containing an optional stabilizer and an optional surfactant, such as water, for example deionized water.

  The mixture may then be heated to evaporate the solvent and then cooled to room temperature. Solvent flushing may be performed at any suitable temperature above the boiling point of the solvent in water, eg, about 60 ° C. to about 100 ° C., about 70 ° C. to about 90 ° C., or about 80 ° C., which flushes out the solvent. The temperature is adjustable.

  After the solvent flush step, the resin / cyanine dye emulsion is measured in a range of about 50 nm to about 600 nm, such as about 100 nm to about 300 nm, as measured using a Honeywell Microtrack UPA 150 particle size analyzer. It should have an average particle size.

  Optional nonionic surfactants such as polyethylene glycol or polyoxyethylene glycol nonylphenyl ether, optional anionic surfactants such as sodium dodecyl sulfonate or sodium dodecyl benzene sulfonate, resins and / or cyanine dyes Or you may prepare an emulsion by stirring a some mixture in water.

  Resin / cyanine dye particles sized with the emulsion so obtained may have a volume average diameter of about 20 nm to about 1200 nm, but particularly include all subranges and individual values are It may be in the range of about 20 nm to about 1200 nm. The emulsion so obtained, typically containing from about 20% to about 60% solids, may be diluted to about 15% solids with water. If a component such as a cyanine dye or resin has not been previously added, or if an additional resin or cyanine dye that was not included in the emulsion process formed above is desired, then the cyanine dye is added to the emulsion at this point. Alternatively, a resin may be added.

  Additional optional ingredients such as additional surfactants, colorants, waxes, and coagulants may be added to the emulsion.

[Aggregation]
The resin-cyanine dye-optional additive mixture is then homogenized, for example, at about 2000 to about 6000 rpm to produce statically bound pre-aggregated particles. Let it form. The statically bonded pre-aggregated particles are then heated to an aggregation temperature below the glass transition temperature of the resin to form aggregated particles. For example, the pre-aggregated particles may be heated to an aggregation temperature of about 40 ° C. to about 60 ° C., such as about 30 ° C. to about 50 ° C. or about 35 ° C. to about 45 ° C. The particles may be held at the aggregation temperature, for example from about 30 minutes to about 600 minutes, such as from about 60 minutes to about 400 minutes, or from about 200 minutes to about 300 minutes.

  At this point, the particle size and distribution may be “frozen” by adjusting the pH and, in some cases, coreless to have a narrow size distribution and controlled particle size. Toner particles may be formed.

  In some cases, a shell may be added to the core by conventional methods prior to coalescence. The shell can be configured to include or not include a cyanine dye. The cyanine dye may be contained in the core and the shell, or may be contained in the shell.

[Coalesence (coalescence)]
After freezing the aggregated particle growth to the desired size, in some cases, the aggregated particle can be heated again to a coalescence temperature above the glass transition temperature of the resin to make the aggregated particle coreless. It is good also as a coreless particle. For example, the aggregated particles may be heated to a coalescence temperature of about 60 ° C to about 100 ° C, such as about 70 ° C to about 90 ° C, or about 75 ° C to about 85 ° C. The particles may be held at the coalescence temperature, for example from about 30 minutes to about 600 minutes, such as from about 60 minutes to about 400 minutes, or from about 200 minutes to about 300 minutes.

  Once the toner particles are formed, they may be isolated from the reaction mixture by any suitable means. Suitable isolation methods include filtration, particle classification and the like.

  In some cases, the formed toner particles may be washed, dried, and / or classified by various conventionally known means. For example, the formed toner particles can be washed using water, deionized water, or other suitable material. The formed toner particles may be similarly dried using, for example, a heat drying oven, a spray dryer, a flash dryer, a pan dryer, a freeze dryer or the like.

  Toner emulsion aggregation particles can be made to have a small particle size (VolD50), for example from about 3 μm to about 10 μm, from about 3.55 μm to about 9 μm, from about 5.2 μm to about 6 μm, or about 5.6 μm. .

Due to the emulsion aggregation process, the toner particles have an excellent particle size distribution, especially when compared to the extended distribution typically exhibited by polymeric particles prepared by grinding (grinding). The toner particles have an upper volumetric geometric standard deviation (GSD _V ) in the range of about 1.15 to about 1.30, such as about 1.18 to about 1.23, and about 1.20 to about 1.40. For example, with a lower geometrical standard deviation (GSD _N ) in the range of about 1.20 to about 1.30. Their GSD values indicate that the particles have a very narrow particle size distribution. The upper GSD is calculated from the cumulative volume percent finer than the measured value and is the ratio of the finer than 84% by volume (D84 _V ) to the finer than 50% by volume (D50 _V ), called D84 / 50 _V There are many things. Lower GSD is calculated from the finer few percent than the measured value, those finer than 50% the number of (D50 _n), a ratio of those finer than 16 percent by the number (D16 _n), called D50 / 16 _n There are many things.

Furthermore, the particles can have a specific shape depending on the process conditions, which can be an important parameter in various end product applications. Therefore, the particle shape should also be adjusted. The particles may have a shape factor of about 105 to about 170, such as about 110 to about 160, SF1 ^* a. Using scanning electron microscopy (SEM), shape factor analysis of particles by SEM is performed and image analysis (IA) test is performed. The average particle shape can be quantified by using the formula of the following shape factor (SF1 ^* a): SF1 ^* a = 100πd ² / (4A), where A is the area of the particle and d is its The main axis. The shape factor of a perfectly circular or spherical particle is exactly 100. The shape factor SF1 ^* a increases as the shape becomes irregular or elongated, or the surface area increases.

  In addition to measuring the shape factor, another metric for measuring particle circularity uses FPIA-2100 or FPIA3000 from Sysmex. This method quantifies the particle shape more quickly. A perfectly round sphere has a circularity of 1.000. In some embodiments, the particles have a circularity of about 0.920 to 0.990, such as about 0.950 to about 0.985, or about 0.950 to about 0.980.

<Other additives>
If desired or necessary, the toner particles may be blended with other optional additives. For example, the toner particles may be blended with a flow aid additive so that such additives are present on the surface of the toner particles. Examples of these additives include: metal oxides such as titanium oxide, silicon oxide, tin oxide, mixtures thereof and the like; colloidal silica and amorphous silica such as Aerosil®. One or more metal salts of fatty acids such as zinc stearate, aluminum oxide, cerium oxide, and mixtures thereof. Each of these external additives may be present in an amount of about 0.1 to about 5% by weight of the toner, such as about 0.25 to about 3%. Suitable additives include those disclosed in US Pat. No. 3,590,000, US Pat. No. 3,800,588, and US Pat. No. 6,214,507. Can be mentioned.

  The toner may have a relative humidity sensitivity of, for example, about 0.5 to about 10, such as about 0.5 to about 5. Relative humidity (RH) sensitivity is the ratio of toner charging under high humidity conditions to charging under low humidity conditions. That is, the RH sensitivity is a toner charge amount of 85% relative humidity and a temperature of about 28 ° C. (A− in this specification) at a relative humidity of 15% and a temperature of about 12 ° C. (referred to herein as C-zone). Therefore, the RH sensitivity is obtained as (C-zone charge amount) / (A-zone charge amount). Ideally, the RH sensitivity of the toner is as close to 1 as possible, which means that the charging performance of the toner is the same under low and high humidity conditions, that is, the charging performance of the toner is the same. It shows that it is hardly affected by relative humidity.

  Toners prepared in accordance with the present disclosure have excellent heat coherency / blocking properties and improved charging performance, Q / m (toner charge / mass of toner charge / mass in the A-zone and C-zone). Ratio) is from about -3 to about -60 microcoulombs per gram, for example from about -4 to about -50 microcoulombs per gram. Such toners may have a heat cohesion starting point greater than about 50 ° C., such as greater than about 52 ° C. Such toners have significantly higher heat cohesion than the corresponding toners. The corresponding toner is a toner having the same or similar components except that it does not contain a cyanine dye component. The high heat cohesion improves the toner blocking performance. For example, a toner comprising a cyanine dye component of the present disclosure is about 3 ° C. to about 8 ° C., such as about 4 ° C. to about 7 ° C., or about 5 ° C. to about 5 ° C., compared to a corresponding toner that does not contain a cyanine dye. It has an improved blocking performance of 6 ° C.

  According to the disclosure of the present invention, the chargeability of the toner particles is improved, and therefore less surface additive is required, thereby resulting in a higher final toner chargeability and the charging performance of the device. May meet requirements.

<Developer>
The toner particles may be blended into the developer composition by mixing the toner particles with carrier particles to obtain a two-component developer composition. The toner concentration in the developer may be from about 1 to about 25%, such as from about 2 to about 15% by weight of the total weight of the developer.

[Carrier]
Examples of carrier particles that may be used to mix with toner particles include particles that can triboelectrically obtain a charge of the opposite polarity to that of the toner particles. Examples of suitable carrier particles include granular zircon, granular silicon, glass, steel, nickel, ferrite, iron ferrite, silicon dioxide and the like. Other carriers include those disclosed in U.S. Pat. No. 3,847,604, U.S. Pat. No. 4,937,166, and U.S. Pat. No. 4,935,326. It is done.

  Selected carrier particles may be used in the presence or absence of a coating. The carrier particles may include a core with a coating on the core that may be formed from a mixture of polymers that are not very close to it in the triboelectric series. Coatings include fluoropolymers such as polyvinylidene fluoride resins, styrene, methyl methacrylate terpolymers, and / or silanes such as triethoxysilane, tetrafluoroethylene, and other known coatings. For example, polyvinylidene fluoride (eg, commercially available as KYNAR 301F ™) and / or polymethyl methacrylate (PMMA) having a weight average molecular weight of about 300,000 to about 350,000 ( A coating comprising commercially available from Soken may be used. The polyvinylidene fluoride and PMMA are in a ratio of (about 30 to about 70% by weight) to (about 70 to about 30% by weight), for example (about 40 to about 60% by weight) to (about 60 to about 40% by weight). It is better to mix. The coating may have a coating weight of, for example, from about 0.1 to about 5% by weight of the carrier, for example from about 0.5 to about 2%.

  There are a variety of effective and suitable means that may be used to apply the polymer onto the carrier core particles, such as cascade roll mixing, tumbling, milling, shaking, electrostatic powder cloud spraying. , Fluidized bed method, electrostatic disk processing method, electrostatic curtain method, and combinations thereof. The mixture of carrier core particles and polymer may then be heated so that the polymer melts and melts into the carrier core particles. The coated carrier particles can then be cooled and then classified to the desired particle size.

  Suitable carriers include about 0.5 to about 10 weight percent using processes such as those described in US Pat. No. 5,236,629 and US Pat. No. 5,330,874. Coated with a conductive polymer mixture comprising, for example, about 0.7 to about 5% by weight of, for example, methyl acrylate and carbon black, for example, a steel core having a size of about 25 μm to about 100 μm, for example about 50 μm to about 75 μm Is mentioned.

  The carrier particles may be mixed with the toner particles in various suitable combinations. The concentration is preferably about 1 to about 20% by weight of the toner composition. However, different toner and carrier percentages may be used to obtain a developer composition having the desired properties.

<Comparative Example 1: Control toner containing no IR absorber>
183.25 g of amorphous resin (XP777, polyester resin (propoxylated bisphenol A fumarate resin), available from Reichhold) emulsion (45.84 wt%) and 56.00 g of unsaturated CPE (chlorine) Chlorinated Polyethylene) resin emulsion (UCPE, 30 wt%) was added into a 2 L glass reactor equipped with an overhead stirrer and heating mantle. While homogenizing, 41.82 g of Al ₂ (SO ₄ ) ₃ solution (1 wt%) was added as a flocculant. The mixture was then heated to 47.2 ° C. at 300 rpm for aggregation. The particle size was monitored using a Coulter Counter until the volume average particle size of the core particles was 5.20 μm and the GSD reached 1.23. Then, 85.52 g of the above-described XP777 resin emulsion was added as a shell, and core-shell particles having an average particle size of 6.75 μm and a GSD of 1.22 were obtained. The particle growth was then frozen using 1.615 g EDTA (ethylenediaminetetraacetic acid) (39 wt%) and NaOH (4 wt%) by raising the pH of the reaction slurry to 6.9. I let you. After freezing the particle growth, the reaction mixture was heated to 69.9 ° C. and the pH was lowered to 5.9 for coalescence. After coalescence, the toner was quenched, cooled to room temperature, separated by sieving (25 μm) filtration, washed and lyophilized. The final toner particles had a final particle size of 6.28 μm, a GSD of 1.23, and a circularity of 0.982.

<Example 1: Toner containing 0.2% by weight of NK-2911>
[A. Preparation of emulsion containing resin and NK-2911]
120 g of amorphous resin (XP777) and 0.24 g of NK-2911 IR absorber were weighed into a 2 L beaker containing about 900 g of ethyl acetate. The mixture was stirred at room temperature at about 300 rpm to dissolve the resin and IR absorber in ethyl acetate. 2.56 g of sodium bicarbonate was weighed into a 3 L Pyrex glass flask reactor containing about 700 g of deionized water. Homogenization of the aqueous solution in the 3 liter glass flask reactor was initiated at 4,000 rpm using an IKA Ultra Turrax T50 homogenizer. The resin solution was then slowly poured into the aqueous solution while continuing to homogenize the mixture, the homogenizer speed was increased to 8,000 rpm, and homogenization was carried out for about 30 minutes under these conditions. When homogenization was complete, the glass flask reactor and its contents were placed in a heating mantle and connected to a distillation apparatus. While stirring the mixture at about 275 rpm, the temperature of the mixture was increased to 80 ° C. at a rate of about 1 ° C./min, and ethyl acetate was distilled from the mixture. Stirring of the mixture was continued at 80 ° C. for about 180 minutes and then cooled to room temperature at a rate of about 2 ° C./minute. The reaction product was sieved through a 25 μm sieve. The resin emulsion thus obtained had a solid content in water of about 19.61 weight percent and an average particle size at 135 nm.

[B. Preparation of toner containing 0.2 wt% NK-2911]
367.16 g of an emulsion of the amorphous resin of Example 1a and an IR absorber and 48 g of an unsaturated CPE resin emulsion (UCPE, 30% by weight) in a 2 L glass reactor equipped with an overhead stirrer and heating mantle Added to the inside. While homogenizing, 35.84 g of Al ₂ (SO ₄ ) ₃ solution (1 wt%) was added as a flocculant. The mixture was then heated to 40.8 ° C. at 260 rpm for aggregation. The particle size was monitored using a Coulter Counter until the volume average particle size of the core particles was 4.54 μm and the GSD reached 1.21. Next, when 171.34 g of the above-described resin and IR absorber emulsion was added as a shell, core-shell structured particles having an average particle size of 5.77 μm and a GSD of 1.22 were obtained. The particle growth was then frozen by raising the pH of the reaction slurry to 7.25 using 1.39 g of EDTA (39 wt%) and NaOH (4 wt%). After freezing the particle growth, the reaction mixture was heated to 69 ° C. and the pH was lowered to 5.9 for coalescence. After coalescence, the toner was quenched, cooled to room temperature, separated by sieving (25 μm), washed and lyophilized. The final toner particles had a final particle size of 5.77 μm, a GSD of 1.24, and a circularity of 0.983.

<Example 2: Toner containing 0.2% by weight of NK-4680>
[A. Preparation of emulsion containing resin and NK-4680]
This emulsion was prepared following the same procedure as outlined in Example 1a except that NK4680 was used instead of NK2911 as the IR absorber.

[B. Preparation of toner containing 0.2 wt% NK-4680]
363.09 g of an emulsion of the amorphous resin of Example 2a and an IR absorber and 48 g of an unsaturated CPE resin emulsion (UCPE, 30% by weight) in a 2 L glass reactor equipped with an overhead stirrer and heating mantle Added to the inside. While homogenizing, 35.84 g of Al ₂ (SO ₄ ) ₃ solution (1 wt%) was added as a flocculant. The mixture was then heated to 40.3 ° C. at 250 rpm for aggregation. The particle size was monitored using a Coulter Counter until the volume average particle size of the core particles was 4.63 μm and the GSD reached 1.23. Subsequently, when 169.44 g of the above-described resin and IR absorber emulsion was added as a shell, core-shell structured particles having an average particle size of 5.60 μm and a GSD of 1.23 were obtained. The particle growth was then frozen by raising the pH of the reaction slurry to 7.6 using 1.39 g of EDTA (39 wt%) and NaOH (4 wt%). After freezing the particle growth, the reaction mixture was heated to 69.3 ° C. and the pH was lowered to 5.9 for coalescence. After coalescence, the toner was quenched, cooled to room temperature, separated by sieving (25 μm), washed and lyophilized. The final toner particles had a final particle size of 5.60 μm, a GSD of 1.23, and a circularity of 0.970.

<Example 3: Toner containing 0.2 wt% S-0813>
[A. Preparation of emulsion containing resin and S-0813]
This emulsion was prepared according to the same procedure as outlined in Examples 1a and 2a except that S-0813 was used in place of NK2911 or NK-4680 as the IR absorber.

[B. Preparation of toner containing 0.2% by weight of S-0813]
311.02 g of an emulsion of the amorphous resin of Example 3a and an IR absorber and 48 g of an unsaturated CPE resin emulsion (UCPE, 30% by weight) in a 2 L glass reactor equipped with an overhead stirrer and heating mantle Added to the inside. While homogenizing, 35.84 g of Al ₂ (SO ₄ ) ₃ solution (1 wt%) was added as a flocculant. The mixture was then heated to 43.1 ° C. at 300 rpm for aggregation. The particle size was monitored using a Coulter Counter until the volume average particle size of the core particles was 4.68 μm and the GSD reached 1.23. Then, 145.14 g of the above-mentioned resin and IR absorber emulsion was added as a shell to obtain core-shell structured particles having an average particle size of 5.96 μm and a GSD of 1.25. The particle growth was then frozen by using 1.39 g EDTA (39 wt%) and NaOH (4 wt%) to raise the pH of the reaction slurry to 6.89. After freezing the particle growth, the reaction mixture was heated to 74.2 ° C. and the pH was lowered to 5.9 for coalescence. After coalescence, the toner was quenched, cooled to room temperature, separated by sieving (25 μm), washed and lyophilized. The final toner particles had a final particle size of 6.41 μm, a GSD of 1.27, and a circularity of 0.981.

  The toner particles of Comparative Example 1 and Examples 1 to 3 are summarized in Table 1 below.

  Surprisingly, the incorporation of cyanine dyes improved the heat coherence of the toner from 48 ° C. to as high as 56 ° C., with no negative effects on chargeability and cohesion. . The results are summarized in Table 2 below.

  All toner samples were melted using a non-contact heating test fixture using a Heraerus IR emitter. The gloss results of the melted toner are summarized in Table 3 below. Examples 1 to 3 have desirable high gloss as compared with Comparative Example 1.

  The minimum melting temperature (MFT) was not measured because it is considered that the toner MFT is not affected because only a small amount of 0.2% by weight of cyanine dye is incorporated into the toner. is there.

Claims (3)

Toner particles,
An amorphous resin;
Crystalline resin;
A cyanine dye,
Toner particles containing. Toner particles,
An amorphous resin;
Crystalline resin;
A cyanine dye,
Including
Toner particles having a heat coherency that is 3 to 8 ° C. higher than the corresponding toner particles that do not contain the cyanine dye. A method for producing toner particles, the method comprising:
Emulsifying an amorphous resin, a crystalline resin, a cyanine dye, an optional colorant, and an optional wax to form pre-aggregated particles;
Aggregating the pre-aggregated particles to form aggregated particles;
Coreless the aggregated particles to form coreless particles;
Isolating the coreless particles;
A method for producing toner particles comprising: